Laser coagulation of an eye structure or a body surface from a remote location

ABSTRACT

An integral laser imaging and coagulation apparatus, and associated systems and methods that allow a physician (e.g., a surgeon) to perform laser surgical procedures on an eye structure or a body surface with an integral laser imaging and coagulation apparatus disposed at a first (i.e. local) location from a control system disposed at a second (i.e. remote) location, e.g., a physician&#39;s office. In some embodiments, communication between the integral laser imaging and coagulation apparatus and control system is achieved via the Internet®.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation-in-part of U.S. patent application Ser. No.13/573,100, filed Aug. 20, 2012, which is a continuation-in-part of U.S.patent application Ser. No. 12/925,518, filed Oct. 22, 2010, whichclaims the benefit of U.S. Provisional Application No. 61/455,111, filedOct. 13, 2010; the disclosure of each of which is hereby incorporated byreference as if set forth in their entirety herein.

FIELD OF THE INVENTION

The present invention relates to methods and systems for lasercoagulation of the eye or a body surface. More particularly, the presentinvention relates to non-invasive and non-contact methods and systemsfor laser coagulation of predetermined portions of the biologicalorganism in the eye; particularly, the retina, or an external bodysurface

BACKGROUND OF THE INVENTION

As is well known in the art, various eye disorders, such as diabeticretinopathy, vascular occlusion, neovascularization and age maculardegeneration, can, and in most instances will, have an adverse effect onthe retina. Indeed, if not treated at the appropriate stage, noteddiseases, particularly, diabetic retinopathy, can lead to severe lossesin vision.

Various methods and systems have thus been developed to aid in thediagnosis of the noted eye diseases. The method often employed by an eyecare specialist, such as an ophthalmologist, is to examine the ocularfundus (the inside back surface of the eye containing the retina, bloodvessels, nerve fibers, and other structures) with an ophthalmoscope.

The ophthalmoscope is a small, hand-held device, which, whenappropriately positioned, shines light through a subject's pupil toilluminate the fundus. By properly focusing the light reflected from thesubject's fundus, an examiner can observe the fundus structures.

As is well known in the art, examination of the ocular fundus can alsobe achieved using a fundus or slit lamp camera. Illustrative are theapparatus and systems disclosed in U.S. Pat. Nos. 5,713,047, 5,943,116,5,572,266, 4,838,680, 6,546,198, 6,636,696, 4,247,176, 5,742,374 and6,296,358.

Various method and systems have also been developed to treat eyedisorders, such as diabetic retinopathy, glaucoma and age maculardegeneration. One known method of treating the noted eye disorders, aswell as retinal detachment, is laser coagulation of predeterminedbiological structures of the eye, such as the retina.

As is well known in the art, during laser coagulation of an eyestructure, laser energy is transmitted to the structure to effectcoagulation thereof. A typical laser coagulation system thus includes alaser energy or beam source, such as a beam projector, a slit imageprojector or lamp for forming a slit image on the eye, and observationequipment for observing the slit image and laser spot(s) in the eye.Illustrative are the laser coagulation systems disclosed in U.S. Pat.Nos. 4,759,360 and 4,736,744.

A major drawback associated with each of the noted conventional systems,as well as most known laser coagulation systems (and associatedmethods), is that the conventional slit lamp systems require a contactlens to neutralize the refractive power of the cornea. A contact lens isalso necessary to provide a variable field of view of the retina up to130°.

As is well known in the art, the contact lens must be appropriatelypositioned on the surface of the cornea and held at the desired positionby the specialist, e.g., surgeon, while looking through the slit lampmicroscope.

During this conventional laser coagulation procedure, the contact lensis positioned on the cornea, and held in position by the surgeon so asto permit the surgeon to view the retina through the slit lampmicroscope during the laser application to the retina. In allconventional contact systems, the field of view is limited (e.g.,maximum 50-60 degrees) and the surgeon is required to move the contactlens from one side of the eye to the other side of the eye during theprocedure, and the patient is also required to move his or her eye, inorder to permit the surgeon to see the peripheral retina.

There are several drawbacks associated with the use of a contact lensduring laser coagulation. A major drawback is that the use of a contactlens requires topical anesthesia and a dilated pupil for laserapplication. As is well known in the art, a contact lens can, and inmany instances will, cause corneal abrasion on an anesthetized cornea.

A further drawback associated with conventional laser coagulationprocedures is that the laser procedures are dependent on the steadinessof the physician's hands and the subject's head.

Another apparatus that is often used for laser energy delivery to theperipheral retina is the indirect ophthalmoscope. Use of the indirectophthalmoscope requires a physician to hold an appropriate convex lensin front of the eye (pupil) with one hand to focus the laser beam on theretina, while the eye is indented with another hand to bring theperipheral retina into the field of view for laser application.

In the indirect ophthalmoscopy technique, which is an alternativeconventional method, the physician (i.e., surgeon) does not place acontact lens on the cornea, but rather he or she has to indent theperipheral part of the eye with an indenter (or scleral depressor) tobring the peripheral retinal areas into view, and additionally, thepatient has to move the eye side to side.

Although laser delivery with an indirect ophthalmoscope eliminates theneed for a contact lens, there are still drawbacks and disadvantagesassociated with use of an indirect ophthalmoscope. A major drawback isthat during laser delivery (and, hence, coagulation of a desired eyestructure), the ophthalmoscope is often carried on the physician's headfor 30-60 mins. This extended period causes extreme fatigue for thephysician.

The indentation of the eye for the extended period is also veryunpleasant for the subject or patient.

A further drawback associated with the use of an indirect ophthalmoscopefor laser coagulation is that the indirect ophthalmoscope does notprovide a retained record or documentation for future evaluation.Further, in most instances, the subject typically requires subsequentfundus photography.

None of the abovedescribed conventional methods are suitable for remotelaser application because they are limited in their field of view(typically 50-60 degrees). Also, the eye movement that is needed withthese systems to view the entire retina renders them unsuitable forremote applications.

It would thus be desirable to provide non-contact systems and methodsfor laser coagulation of eye structures to treat eye disorders, and arecapable of being effectively utilized to treat patients located at aremote site.

It is therefore an object of the present invention to providenon-contact systems and methods for laser coagulation of eye structuresthat substantially reduce or overcome the noted drawbacks anddisadvantages associated with conventional contact-based lasercoagulation systems and methods.

It is another object of the present invention to provide non-contactapparatus, systems and methods for laser imaging and coagulation of aneye structure.

It is another object of the present invention to provide non-contactapparatus, systems and methods for laser imaging and coagulation of theretina and its periphery to treat retina and choroideal disorders and/ordiseases.

SUMMARY OF THE INVENTION

The present invention is directed to laser imaging and coagulationapparatus, systems and methods that allow an eye specialist, e.g., anophthalmologist or surgeon, to perform laser surgery on an eyestructure, e.g. retina, with an integral laser imaging and coagulationapparatus disposed at a first (i.e. local) location from a controlsystem disposed at a second (i.e. remote) location, e.g., a physician'soffice. The laser imaging and coagulation apparatus, systems and methodsof the invention thus make it possible for an ophthalmologist to screenand perform laser surgery to treat various eye disorders, including,without limitation, diabetic retinopathy, vascular occlusion,neovascularization and age macular degeneration from a geographicallyremote location.

In one embodiment of the invention, the laser coagulation systemincludes

-   -   (i) at least a first laser-imaging system disposed at a first        location, the first laser-imaging system including a first        laser-imaging apparatus, a photoacoustic system, a first        processor and a local control module,    -   the first laser-imaging apparatus including a wide angle digital        image acquisition system for acquiring digital images of a        subject's eye structure and a laser generation system for        transmitting an aiming laser beam and at least a first        coagulation laser beam to the eye structure, the first        coagulation laser beam having a first laser energy,    -   the photoacoustic system being configured to measure temperature        of eye structure tissue subjected to the first laser energy,    -   the local control module including local operation, local        operation and performance simulation and local safety and        verification sub-modules; and    -   (ii) a central control system disposed at a remote site, the        central control system including a second processor and a remote        control module,    -   the remote control module including remote operation, remote        operation and performance simulation, and remote safety and        verification sub-modules,    -   the remote operations sub-module being configured to facilitate        communications between a remote physician and the remote        processor, and perform a laser coagulation procedure on the eye        structure in an actual control mode.

In some embodiments of the invention, the local operation sub-module isconfigured to acquire at least a first eye structure image from thedigital image acquisition system and transmit the first eye structureimage to the remote site, receive a target laser transmission area andlaser transmission parameters from a remote physician, apply an activecontour algorithm to partition the first eye structure image into a gridmap, perform a scatter laser (focal or grid) coagulation of the eyestructure under the remote physician's command, acquire a plurality ofpost-procedure eye structure images, and transmit the post-procedure eyestructure images to the remote site for evaluation and verification oftreatment.

In some embodiments, the remote operations sub-module is furtherconfigured to execute a virtual treatment of the eye structure andperform a test surgical procedure in association with the localoperation and performance simulation sub-module.

In some embodiments, the remote operation and performance simulationsub-module is configured to test performance parameters of the localoperation module and perform virtual treatment of the eye structure bythe remote physician.

In some embodiments of the invention, the photoacoustic system isconfigured to control the laser generation system.

In one embodiment of the invention, the eye structure comprises theretina.

In some embodiments of the invention, the laser coagulation system alsoincludes eye tracking means for tracking movement of the eye.

In some embodiments of the invention, the laser coagulation system alsoincludes facial recognition means for identifying and/or verifying theidentity of the subject.

In one embodiment, communication by and between the central controlsystem and the laser-imaging apparatus is achieved via the Internet®

In another embodiment, the laser coagulation system includes:

a local control system disposed at a first location and a centralcontrol system disposed at a remote site, the remote site being at asecond location;

at least a first laser-imaging system disposed at the first location,the laser-imaging system including a laser-imaging apparatus, a firstprocessor and a local control module;

the laser-imaging apparatus including a digital image acquisition systemconfigured to acquire digital images of the eye structure or the bodysurface, the local control module including local operation, localoperation and performance simulation, and local safety and verificationsub-modules;

a laser generation system configured to generate and transmit at least afirst aiming laser beam and at least a first coagulation laser beam, andmeans for controlling the digital image acquisition system and the lasergeneration system;

a central control system disposed at the remote site, the centralcontrol system including a second processor and a remote control module,the remote control module including remote operation, remote operationand performance simulation, and remote safety and verificationsub-modules; and

-   -   the remote operation sub-module being configured to facilitate        communications between a remote physician and the second        processor, and perform a laser coagulation procedure on the eye        structure or the body surface in an actual control mode, the        remote operation sub-module including a touchscreen interface        configured to enable the remote physician to draw a target laser        treatment area or areas on a digitized image of the eye        structure or the body surface.

In yet another embodiment, the laser coagulation includes:

a local control system disposed at a first location and a centralcontrol system disposed at a remote site, the remote site being at asecond location;

at least a first laser-imaging system disposed at the first location,the laser-imaging system including a laser-imaging apparatus, a firstprocessor and a local control module;

the laser-imaging apparatus including a wide angle digital imageacquisition system configured to acquire digital images of the eyestructure or the body surface, the local control module including localoperation, local operation and performance simulation, and local safetyand verification sub-modules;

a laser generation system configured to generate and transmit at least afirst aiming laser beam and at least a first coagulation laser beam, andmeans for controlling the digital image acquisition system and the lasergeneration system, the first coagulation laser beam transmitting laserenergy in the form of a plurality of pulses having a pulse duration inthe range between approximately one femtosecond and approximately fourseconds, inclusive;

a central control system disposed at the remote site, the centralcontrol system including a second processor and a remote control module,the remote control module including remote operation, remote operationand performance simulation, and remote safety and verificationsub-modules; and

the remote operation sub-module being configured to facilitatecommunications between a remote physician and the second processor, andperform a laser coagulation procedure on the eye structure or the bodysurface in an actual control mode.

In still another embodiment, the laser coagulation system includes:

a local control system disposed at a first location and a centralcontrol system disposed at a remote site, the remote site being at asecond location;

at least a first laser-imaging system disposed at the first location,the laser-imaging system including a laser-imaging apparatus, a firstprocessor and a local control module;

the laser-imaging apparatus including a wide angle digital imageacquisition and storage system configured to take and store digitalimages of the retina, the digital image acquisition and storage systemfurther including means for transmitting digital images;

a laser generation system configured to generate and transmit at least afirst aiming laser beam and at least a first coagulation laser beam, andmeans for controlling the digital image acquisition and storage systemand the laser generation system;

the local control module including a local operation sub-module, a localoperation and performance simulation sub-module, the local operationsub-module configured to acquire at least a first digitized image of theeye structure or the body surface from the digital image acquisition andstorage system and transmit the first digitized image to the remotesite, the local operation sub-module further configured to receive atarget laser transmission area or areas and laser transmissionparameters from a remote physician, and determine a treatment area orpattern of spots on the first digitized image for application of thefirst coagulation laser beam, the local operation sub-moduleadditionally configured to perform a laser coagulation of the eyestructure or the body surface under the remote physician's command inwhich the first coagulation laser beam is applied to the treatment areaor each of the spots in the pattern, the local operation and performancesimulation sub-module configured to facilitate the testing of the systemprior to its operation in an actual control mode by replacing an actualeye structure or body surface of the subject with the first digitizedimage or a second digitized image of the subject's eye structure or bodysurface;

the central control system being in communication with the laser-imagingapparatus, including a remote control module and a second processorconfigured to receive and process command signals from the remotephysician and transmit the command signals to the local control module;and

the remote control module including a remote operation sub-moduleconfigured to facilitate communications between the remote physician andthe second processor, the remote operation sub-module, in associationwith the local operation and performance simulation sub-module, furtherconfigured to execute a virtual treatment of the eye structure or thebody surface, perform a test surgical procedure, and perform a fullyautomated and continuous laser coagulation procedure over the entirearea of the eye structure or the body surface in the actual controlmode.

In yet another embodiment, the laser coagulation system includes:

a local control system disposed at a first location and a centralcontrol system disposed at a remote site, the remote site being at asecond location;

at least a first laser-imaging system, the laser-imaging systemincluding a laser-imaging apparatus, a first processor and a localcontrol module;

the laser-imaging apparatus including a wide angle digital imageacquisition and storage system configured to take and store digitalimages of the retina, the digital image acquisition and storage systemincluding at least one retinal viewing camera that provides a field ofview of the retina in a range between 160° and 200°, the digital imageacquisition and storage system further including means for transmittingdigital images;

a laser generation system configured to generate and transmit at least afirst aiming laser beam and at least a first coagulation laser beam, andmeans for controlling the digital image acquisition and storage systemand the laser generation system;

the local control module including a local operation sub-module, a localoperation and performance simulation sub-module, and a local safety andverification sub-module, the local operation sub-module configured toacquire at least a first retinal image of the retina from the digitalimage acquisition and storage system and transmit the first retinalimage to the remote site, the local operation sub-module furtherconfigured to receive a target laser transmission area and lasertransmission parameters from a remote physician, and determine a patternof spots on the first retinal image for application of the firstcoagulation laser beam, the local operation sub-module additionallyconfigured to perform a scatter laser coagulation of the retina underthe remote physician's command in which the first coagulation laser beamis applied to each of the spots in the pattern, acquire a plurality ofpost-procedure retinal images, and transmit the post-procedure retinalimages to the remote site for evaluation and verification of treatment,the local operation and performance simulation sub-module configured tofacilitate the testing of the system prior to its operation in an actualcontrol mode by replacing an actual eye of the subject with a digitizedfundus image of the subject's eye;

the central control system being in communication with the laser-imagingapparatus, and including a remote control module and a second processorconfigured to receive and process command signals from the remotephysician and transmit the command signals to the local control module;

the remote control module including a remote operation sub-moduleconfigured to facilitate communications between the remote physician andthe second processor, execute a virtual treatment of the retina, performa test surgical procedure, and perform a fully automated and continuouslaser coagulation procedure over the entire area of the retina in theactual control mode;

the remote control module further including a remote operation andperformance simulation sub-module and a remote safety and verificationsub-module, the remote operation and performance simulation sub-moduleconfigured to test performance parameters of the local operation moduleand perform a treatment simulation of the retina by the remote physicianwhile simulating eye movement of the subject by displacing the digitizedfundus image of the subject's eye in accordance with a plurality ofrandom variables;

the local and remote safety and verification sub-modules includingphysical, logical and medical safety constraints for safe operation ofthe system; and

wherein the system for laser coagulation of the retina is in the form ofa non-contact system that does not require the use of a contact lens.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features and advantages will become apparent from the followingand more particular description of the preferred embodiments of theinvention, as illustrated in the accompanying drawings, and in whichlike referenced characters generally refer to the same parts or elementsthroughout the views, and in which:

FIG. 1 is an illustration of a human eye showing the major structuresthereof;

FIG. 2 is a schematic illustration of one embodiment of a laser-imagingapparatus, in accordance with the invention;

FIG. 3 is a schematic illustration of another embodiment of alaser-imaging apparatus, showing the elliptical mirror thereof, inaccordance with the invention;

FIG. 4 is a schematic illustration of a photoacoustic system, inaccordance with the invention;

FIG. 5 is a schematic illustration of one embodiment of a laser-imagingsystem, in accordance with the invention;

FIG. 6 is another schematic illustration of the laser-imaging systemshown in FIG. 5, showing the local and remote modules thereof, inaccordance with one embodiment of the invention;

FIG. 7 is an illustration of a human retina, showing an oval areaencompassing the target area on the retina for laser transmission, inaccordance with one embodiment of the invention;

FIG. 8 is an illustration of a human retina, showing the distribution oflaser spots resulting from a virtual treatment of the retina, inaccordance with one embodiment of the invention;

FIG. 9 is an illustration of a human retina, showing simulationvariables associated with movement of the eye, in accordance with oneembodiment of the invention;

FIG. 10 is an illustration of a human retina, showing a generated gridmap on the retina, in accordance with one embodiment of the invention;

FIG. 11 is an illustration of a human retina, showing a large area ofthe fundus that is to be coagulated, in accordance with one embodimentof the invention;

FIG. 12 is an illustration of a human retina, showing localized areas ofthe fundus that are to be coagulated, in accordance with one embodimentof the invention;

FIG. 13 is an illustration of a human retina, showing single, localizedspots of the fundus that are to be coagulated, in accordance with oneembodiment of the invention; and

FIG. 14 is an illustration of a human face, showing an area of a skinlesion that is marked for laser application.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Before describing the present invention in detail, it is to beunderstood that this invention is not limited to particularlyexemplified apparatus, systems, structures or methods as such may, ofcourse, vary. Thus, although a number of apparatus, systems and methodssimilar or equivalent to those described herein can be used in thepractice of the present invention, the preferred apparatus, systems,structures and methods are described herein.

It is also to be understood that the terminology used herein is for thepurpose of describing particular embodiments of the invention only andis not intended to be limiting.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one having ordinaryskill in the art to which the invention pertains.

Further, all publications, patents and patent applications cited herein,whether supra or infra, are hereby incorporated by reference in theirentirety.

Finally, as used in this specification and the appended claims, thesingular forms “a, “an” and “the” include plural referents unless thecontent clearly dictates otherwise. Thus, for example, reference to “alaser image” includes two or more such images and the like.

DEFINITIONS

The terms “eye disorder” and “eye disease” are used interchangeablyherein and mean and include, without limitation, diabetic retinopathy,vascular occlusion, neovascularization, retinal detachment, neoplastictissue, ischemic retina, retinopathy of prematurity and age relatedmacular degeneration.

The following disclosure is provided to further explain in an enablingfashion the best modes of performing one or more embodiments of thepresent invention. The disclosure is further offered to enhance anunderstanding and appreciation for the inventive principles andadvantages thereof, rather than to limit in any manner the invention.The invention is defined solely by the appended claims including anyamendments made during the pendency of this application and allequivalents of those claims as issued.

As will readily be appreciated by one having ordinary skill in the art,the present invention substantially reduces or eliminates thedisadvantages and drawbacks associated with conventional systems andmethods for coagulating eye structures to treat eye disorders.

In overview, the present disclosure is directed to laser imaging andcoagulation apparatus, systems and methods that allow an eye specialist,e.g., an ophthalmologist or surgeon, to perform laser retinal surgicalprocedures, such as laser or tissue coagulation, with an integral laserimaging and coagulation apparatus disposed at a first (i.e. local)location from a control system disposed at a second (i.e. remote)location, e.g., a physician's office.

By the term “laser coagulation”, as used herein, it is meant to mean andinclude, without limitation, selective absorbance of transmitted lightenergy (having a visible green wavelength) by hemoglobin in biologicaltissue and, hence, sealing of blood vessels in the tissue. In apreferred embodiment of the invention, the wavelength of the transmittedenergy (referred to herein as a “treatment or coagulative laser beam”)is in the range of approximately 400-1650 nm, more preferably, in therange of approximately 530-670 nm.

Although the present invention is directed to thermotherapy ofbiological tissue by laser energy, it is to be understood the inventionis not limited to such form of energy. Indeed, as will readily beappreciated by one having ordinary skill in the art, the thermotherapyof biological tissue described herein, i.e. coagulation of selective eyestructures, can also be achieved via the application of electromagneticradiation, and radio frequency and ultrasound energy.

It is further to be understood that, although the biological tissuesubject to the thermotherapy (i.e. coagulation), in accordance with thepresent invention, comprises the retina, the invention is not limitedsolely to thermotherapy of the retina. According to the invention, thethermotherapy of the present invention can be employed to coagulate anyeye structure.

The laser-imaging apparatus, systems and methods of the invention, andlaser energy transmitted thereby, can thus be employed to treat variouseye disorders, including, without limitation, diabetic retinopathy,vascular occlusion, neovascularization, retinal detachment, neoplastictissue, ischemic retina, retinopathy of prematurity and age relatedmacular degeneration.

The laser-imaging apparatus, systems and methods of the invention, andlaser energy transmitted thereby, can also be readily employed inrefractive surgical procedures to, for example, perform corneal surfaceablation using an eximer or femtosecond laser, LASIK procedures, and/orlid surface and surrounding tissue tightening using an infrared laser.

The laser-imaging apparatus, systems and methods of the invention, andlaser energy transmitted thereby, can also be readily employed incosmetic surgical procedures to, for example, remove skin lesions andperform skin resurfacing.

Before describing the invention in detail, the following briefdescription of the various anatomical features of the eye is provided,which will help in the understanding of the various features of theinvention:

Referring to FIG. 1, the cornea 10, which is the transparent window thatcovers the front of the eye 100, is a lens-like structure that providestwo-thirds of the focusing power of the eye.

The cornea 10 is slightly oval, having an average diameter of about 12mm horizontally and 11 mm vertically. The central thickness of thecornea 10 is approximately 550 μM.

The sclera 16 is the white region of the eye, i.e. posterior five sixthsof the globe. It is the tough, avascular, outer fibrous layer of the eyethat forms a protective envelope. The sclera is mostly composed of densecollagen fibrils that are irregular in size and arrangement (as opposedto the cornea). The extraocular muscles insert into the sclera behindthe limbus.

The sclera 16 can be subdivided into 3 layers: the episclera, scleraproper and lamina fusca. The episclera is the most external layer. It isa loose connective tissue adjacent to the periorbital fat and is wellvascularized.

The sclera proper, also called tenon's capsule, is the layer that givesthe eye 100 its toughness. The sclera proper is avascular and composedof dense type I and III collagen.

The lamina fusca is the inner aspect of the sclera 16. It is locatedadjacent to the choroid and contains thin collagen fibers and pigmentcells.

The pars plana is a discrete area of the sclera 16. This area is avirtually concentric ring that is located between 2 mm and 4 mm awayfrom the cornea 10.

The vitreous humor or vitreous 12 is the largest chamber of the eye 100(i.e. ˜4.5 ml). The vitreous 12 is a viscous transparent gel composedmostly of water. Unlike the fluid contained in the frontal parts of theeye (e.g., aqueous humor, discussed below), which are continuouslyreplenished, the transparent gel in the vitreous chamber is stagnant.

As is well known in the art, the vitreous humor 12 also contains arandom network of thin collagen fibers, mucopolysaccharides andhyaluronic acid.

The aqueous humor 14 occupies the anterior chamber 18 of the eye 100.The aqueous humor 14 has a volume of about 0.6 mL and provides nutrientsto the cornea 10 and lens 28.

One of the most important functions of the aqueous humor 14 is tomaintain IOP by the rate of its production and drainage.

The additional parts of the eye that are illustrated in FIG. 1 comprisethe uvea, and structures thereof, lens 28 and retina 30.

The uvea refers to the pigmented layer of the eye 100 and is made up ofthree distinct structures: the iris 22, ciliary body, and choroid 24.The iris 22 is the annular skirt of tissue in the anterior chamber 18that functions as an aperture. The pupil is the central opening in theiris 22.

The ciliary body is the 6 mm portion of uvea between the iris 22 andchoroid 24. The ciliary body is attached to the sclera 16 at the scleralspur. It is composed of two zones: the anterior 2 mm pars plicata, whichcontains the ciliary muscle 26, vessels, and processes, and theposterior 4 mm pars plana.

The ciliary muscle 26 controls accommodation (focusing) of the lens 28,while the ciliary processes suspend the lens 28 (from small fibers, i.e.zonules) and produce the aqueous humor 14 (the fluid that fills theanterior and posterior chambers and maintains intraocular pressure).

The choroid 24 is the tissue disposed between the sclera 16 and retina30. The choroid 24 is attached to the sclera 16 at the optic nerve 20and scleral spur. This highly vascular tissue supplies nutrients to theretinal pigment epithelium (RPE) and outer retinal layers.

The layers of the choroid 24 (from inner to outer) include the Bruch'smembrane, choriocapillaris and stroma. Bruch's membrane separates theRPE from the choroid 24 and is a permeable layer composed of thebasement membrane of each, with collagen and elastic tissues in themiddle.

The crystalline lens 28, located between the posterior chamber and thevitreous cavity, separates the anterior and posterior segments of theeye 100. Zonular fibers suspend the lens from the ciliary body andenable the ciliary muscle to focus the lens 28 by changing its shape.

The retina 30 is the delicate transparent light sensing inner layer ofthe eye 100. The retina 30 faces the vitreous and consists of two basiclayers: the neural retina and retinal pigment epithelium. The neuralretina is the inner layer. The retinal pigment epithelium is the outerlayer that rests on Bruch's membrane and choroid 24.

As indicated above, conventional slit lamp systems, which are oftenemployed to treat various eye disorders, such as diabetic retinopathy,require a contact lens to neutralize the refractive power of the corneaand to provide a variable field of view of the retina.

The length of time to perform a surgical procedure with a conventionalslit lamp system is also presently in the range of 30 minutes to anhour. There is thus an increased percentage of probable error due to thelaser photo-coagulation being controlled manually, i.e. by thephysician's hand, and the potential eye movements from the patientduring this extended period of time.

The present invention substantially reduces or eliminates thedisadvantages and drawbacks associated with conventional slit lampsystems and associated methods. As discussed in detail herein, thelaser-imaging apparatus include means for taking and storing digitalimages of the target eye structure(s), which can be retrieved on amonitor for diagnosis and defining the area of treatment. In someembodiments, the laser-imaging apparatus (and systems) of the inventionthus include a retinal camera (e.g., Topcon, Zeiss, Kowa or preferably awide angle viewing system having an elliptical mirror), which, in someembodiments, is modified with a wide-angle lens.

A wide field scanning laser-imaging apparatus, such as the laseropthalmoscope disclosed in U.S. Pat. No. 5,815,242, can also be employedto provide images of the fundus, particularly, the retina. The notedlaser-imaging apparatus can also be readily modified for lasercoagulation procedures in one or multiple health care applications oradditional vision care offices.

According to the invention, the viewing light can comprise a white lightfrom a flush light, laser source or one or more scanning lasers withcompensatory wavelengths in the range of approximately 190 nm-10,000 nm,more preferably, in the range of approximately 400-1060 nm, to obtain afundus photograph.

According to the invention, the retinal camera is connected to lasertransmission means (or a laser system) that is adapted to generate andtransmit laser energy that is sufficient to coagulate any desiredportion of the retina using a monitor's touch screen.

In a preferred embodiment of the invention, the laser-imaging apparatusincorporates aiming and treatment laser generating and transmissionmeans into an existing camera (e.g., Topcon, Zeiss, etc.) or a wideangle viewing system/camera, such as the laser opthalmoscope disclosedin U.S. Pat. No. 5,815,242. The laser-imaging apparatus also includescontrol means for controlling the aiming and treatment laser means, andthe camera.

Preferably, the transmitted laser beam passes through the optical pathof the viewing apparatus (or system) and is preferably reflected off ofan elliptical mirror in the camera (in which the imaging light isfocused toward the pupil or slightly behind the pupil), providing afield of view greater than approximately 200°.

Referring now to FIG. 2, there is shown one embodiment of alaser-imaging apparatus of the invention. As illustrated in FIG. 2, thelaser-imaging apparatus 200 includes a Topcon digital camera 202,scanning laser visualization means 204 and internal laser generation andtransmission means (i.e. coagulation means) 206. The laser-imagingapparatus 200 further includes a refracting lens 203, at least onetwo-way mirror 208 and a plurality of appropriately positionedreflecting mirrors 201 a-201 c.

Referring now to FIG. 3, in an alternative embodiment, a wide anglecamera equipped with an elliptical mirror 220 is employed. According tothe invention, the illustrated wide angle camera provides an improvedrange of between approximately 150° and approximately 200°, inclusive,(or an improved range between 150° and 200°, inclusive) of the retinafor optimal treatment.

In some embodiments, the concave, elliptical mirror 220 illustrated inFIG. 3 is configured to oscillate (or wobble) slightly in order to shiftthe focal point of the mirror 220 slightly from one side of the pupil tothe other side, thereby permitting the scanning light (e.g., lowcoherent wavelengths, etc.) inside the eye to cover a larger peripheralfield than possible without oscillation. An exemplary imaging system forimaging the central and peripheral retina, which employs such anoscillating concave mirror, is disclosed in Applicant's U.S. Pat. No.8,070,289; which is incorporated by reference herein in its entirety.

In other embodiments, the concave, elliptical mirror 220 illustrated inFIG. 3 is stationary and is not configured to oscillate or wobble. It isalso to be understood that the concave mirror 220 can be provided in theform of circular mirror, as well as an elliptical mirror.

FIG. 3 shows the path of the viewing/imaging scanning laser beams 214 asthey are reflected and pass through the focal point of the mirror behindthe pupil (Black) toward the retina. As illustrated in FIG. 3, thecoagulative laser beam 216 preferably passes through the same path asthe viewing/imaging beams 214.

In some embodiments of the invention, the laser-imaging apparatus of theinvention also includes an optical coherence tomography (OCT) means.

Preferably, the rays reflected back from the retina pass through thesame pathway and form a digital image that can be observed on themonitor.

According to the invention, the coagulative laser beam is also scannedover the retinal area via the same light path as used for theobservation and documentation.

The integration of the aiming and treatment laser generating andtransmission means with a camera requires the introduction of precisionmotorized optical fixtures. An opto-mechanical system having an integralcontrol system is thus provided to control and/or position the targetspot of the laser beam(s) in x and y directions within the eye. Thesystem is designed and adapted to interface with joystick commandsand/or computer/monitor touch screen commands, for local and remotecontrol of the aiming and treatment (or coagulative) lasertransmissions, respectively.

In some embodiments of the invention, the control means for positioningthe laser transmissions (or beams) within the eye consists of two maincomponents. The first component is adapted to move the beams in thex-direction. The second component is adapted to move the beams in they-direction.

Preferably, movement in the y-direction is provided by a mirroredsurface disposed in the optical path of the camera. This y-direction,motorized fixture provides precise movement of the mirrored surface,while still allowing diagnostic and treatment images to be seen throughthe retinal camera.

In some embodiments of the invention, producing the x-direction movementinvolves physically moving the laser unit; the movement of the laserbeing either translational or rotational. Various conventional means ofmotorized movement can also be employed to provide movement in thex-direction.

In a preferred embodiment, the laser-imaging apparatus is incommunication with another remote system via the Internet®, whereby thelaser-imaging apparatus can be controlled by a physician at the remotesite (e.g., medical center).

According to the invention, location of laser energy or beam applicationcan be from 5-200° of the retina. In some embodiments, location of laserenergy application is preferably 30-200° of the retina.

In some embodiments of the invention, the transmitted coagulative laserenergy (or beam(s)) has a wavelength in the range of approximately400-1650 nm, more preferably, in the range of approximately 530-670 nm.The laser (or laser energy) can also be transmitted in a pulsed manneror continuously.

According to the invention, the laser spot size can be in the range ofapproximately 10 micron-1500 micron.

According to the invention, exposure time of the laser energyapplication can be in the range of approximately 1 femto-seconds to 1000seconds.

In some embodiments of the invention, the laser-imaging apparatus 200includes a photoacoustic system that can measure the temperature insidethe eye tissue during and after laser scanning. A preferredphotoacoustic system is disclosed in Applicant's U.S. Pat. No.8,121,663; which is incorporated by reference herein in its entirety.

As set forth in detail in the '663 patent, the photoacoustic system isadapted to record the sonic waves that are generated by heating eyetissue, e.g. retina tissue. This provides precise information of thetemperature generated as a result of the laser transmission, i.e.coagulative laser energy.

Advantageously, the photoacoustic system enables the temperaturegenerated at the treatment site to be measured. As a result, the systemis capable of balancing the energy of the laser system so that thecoagulation is performed in a uniform fashion at the desired area,without such balancing one could have some lesions stronger than othersdepending on the degree of the pigmentation of the retina at theparticular site (i.e., if the site absorbs more laser light).

Referring now to FIG. 4, there is shown one embodiment of aphotoacoustic system 80. As illustrated in FIG. 4, the photoacousticsystem 80 includes a laser source 88, an ultrasonic detector 89, and aprobe module 82. The probe module 82 includes an objective lensstructure 84, which is preferably coupled to the light source 88 via afiber optic connection or other light transmitter. Alternatively, thelight source can be incorporated into the probe module 82.

According to the invention, the light source 88 can comprise a laser,laser diode or superluminescent diode (SLD), as appropriate forgenerating the desired light wavelength and intensity. The light canalso be delivered as pulses or as modulated radiation.

As further illustrated in FIG. 4, the probe module 82 further containsan ultrasound transducer 86 that is adapted to detect the photoacousticwaves that are generated as a result of the absorption of energy fromthe light emitted by the objective lens structure 84. The ultrasoundtransducer 86 is in contact with the eye 100 or an eyelid drawn over theeye.

As light is delivered as pulses or as modulated radiation, pulses ormodulating acoustic signals are generated and returned to the ultrasoundtransducer 86 in probe module 82.

According to the invention, localization of the source of photoacousticsignals can be achieved in various manners. First, localization can beaccomplished by directing the beam from objective lens structure 84 inspecific directions, by moving that structure with micromechanicalactuators, as shown diagrammatically at 85 in FIG. 4, thus targeting aparticular line of points in the eye.

Furthermore, by suitable optics included in objective lens structure 84,the focal point of the emitted light may be moved within the eye to adesired point, such as a point along the retina vasculature, toselectively generate acoustic signals at that desired point. Because theeye is optically transmissive relative to soft tissue, beam focusing andbeam directing are likely to be more accurately performed in the eye,than is the case is soft tissue elsewhere in the body.

To further assist in directionally capturing the photoacoustic signalsgenerated within the eye, a directional transducer array can be used astransducer 86, to control the directionality of reception of ultrasonicenergy, thus further localizing upon a desired source of thermoacousticsignals. Thus, by targeting the focal point of the illuminating light,and also directionally targeting the reception of ultrasonic signals bythe transducer array, thermoacoustic signals from a particular location,such as along the retina, may be specifically targeted.

Overview of Laser-Imaging System

Referring now to FIG. 5, there is shown a schematic diagram of alaser-imaging system 50, according to one embodiment of the invention.As illustrated in FIG. 5, the system 50 includes at least one,preferably, multiple local systems 52, 54, 56 disposed at local sites 51a, 51 b, 51 c; each system 52, 54, 56 including a laser-imagingapparatus (denoted “53”, “55” and “57”), such as the apparatus 200 shownin FIG. 2. In a preferred embodiment of the invention, eachlaser-imaging apparatus 53, 55, 57 includes a photoacoustic system, suchas system 80 discussed above.

Preferably, each laser-imaging apparatus 53, 55, 57 is preferably incommunication with a local control module 62 and control-processingmeans 59 a, such as a personal computer.

In some embodiments of the invention, at least the control-processingmeans 59 a disposed at each local site 51 a, 51 b, 51 c includes facialrecognition means for identifying and/or verifying the identity of asubject or patient. Alternatively, in some embodiments, thecontrol-processing means 59 b disposed at the remote site 51 d(discussed below) includes facial recognition means. In some embodimentsboth control-processing means 59 a, 59 b include facial recognitionmeans.

In some embodiments of the invention, each local system 52, 54, 56 alsoincludes eye tracking means 71 for measuring eye position(s) andmovement. According to the invention, the eye tracking means 71 can bean integral component or feature of the laser-imaging apparatus 53, 55,57 or a separate system or device.

Also disposed at each local site 51 a, 51 b, 51 c during a laserprocedure is a test subject or patient and a physician or technician.

As also illustrated in FIG. 5, the system 50 also includes a remote site58 having a command computer 59 b that is operatively connected to aremote control module 64. Also disposed at the remote site 58 during alaser procedure is a system operator (e.g., retinal surgeon).

As discussed in detail below, communication by and between the localsites 52, 54, 56 and the remote site 58 is preferably facilitated by thelocal and remote control modules 62, 64 and the Internet® 60.

In accordance with one embodiment of the invention, the sequence ofinteractions between the local sites 52, 54, 56 and remote site 58comprises the following:

-   -   Fundus photograph is digitally transmitted to remote site;    -   Image is acquired by remote site and filed in the computer at        remote site;    -   Eye is repositioned in front of the camera, fundus image is        taken for pattern recognition and tracking, and transmitted to        remote site, verified as matching previous, pre-existing image        on file;    -   New image is selected and employed as simulator;    -   Spot size, power level, and time interval between each laser is        chosen;    -   Tracking system (fail-safe) is checked;    -   Fundus laser treatment is performed in virtual mode to establish        the desired laser coagulation; and    -   After choosing spot size and duration of laser application,        power is adjusted to the lowest increment of energy that may or        may not be able to create a response on the patient's eye. The        power of the laser is incrementally increased until the test        spot demonstrates the desired effect.

In a preferred embodiment, the optimum power and, hence, temperaturerequired for a procedure is provided via the photoacoustic system. Thephotoacoustic system is further adapted to maintain the transmittedlaser energy at a fixed, pre-selected level. This particularly resultsin a uniform coagulation of the retina.

Local and Remote Control Modules

Referring now to FIG. 6, there is shown a schematic diagram of a localcontrol module 62 and a remote control module 64, according to oneembodiment of the invention. As illustrated in FIG. 6, the local controlmodule 62 preferably includes three sub-modules: an operation module 65,safety and verification module 66, and an operation and performancesimulation module 67.

The remote control module 64 similarly includes three sub-modules: anoperation module 70, safety and verification module 72, and an operationand performance simulation module 74.

Each of these sub-modules 65, 66, 67 is described below.

Local Operation Module

According to the invention, the local operation module 65 provides alocal technician with an interface to a personal computer for dataacquisition and eye treatment.

According to the invention, the major tasks performed by the localoperation module 65 include the following:

(1) acquiring a plurality (preferably, in the range of 5-7) standardfields of the fundus retinal images and transmission of the images tothe remote site 58;

(2) receiving the oval area encompassing the focused region of theretina outlined by the remote physician (see FIGS. 5 and 7), as well asparameters for the spot size, power and duration of laser application;

(3) applying a snake algorithm (i.e. active contour algorithm) toextract the contours, calculating the corresponding areas between thecontours, and partitioning the image into a grid map (see FIG. 10), as afunction of the specified surgical area and corresponding parameters forlaser application from the remote center. According to the invention,the resolution of the grid is adjusted according to the area between thecontours, whereby the number of nodes between the contours (i.e. theblack points between the two white contours) is large enough to generatein the range of approximately 700-1000 laser spots to ensure the surgeryprecision;

(4) performing the scatter laser coagulation under the remote doctor'scommand. During the process (which is performed in real-time), theKalman filter and mean shift algorithm are preferably integrated todetect and estimate the test subject's eye movement: a) if the movementis under the given safety threshold, the laser system will be adjustedusing a simple proportional-integral-derivative (PID) control algorithmbased on the estimated motion so that it will be focused on the remotelyspecified spot within allowable surgical accuracy, and then the laserwill be applied; b) if the estimated movement is beyond the specifiedsafety threshold, the laser coagulation procedure will be terminatedimmediately and a warning message will be transmitted to the remotecontrol module 64. Step (1), above, will also be repeated until a stopinstruction is received from the remote physician; and

(5) acquiring a plurality (preferably, in the range of 4-5) standardfields of fundus retinal images and transmitting the images to theremote site for evaluation and verification of treatment.

Local Operation and Performance Simulation Module

According to the invention, the local operation and performancesimulation module 67 allows the physician (or technician) to test theentire system 50 (e.g., tracking and interruption functions in the localoperation module 65; communications between local and remote sites;safety and verification modules 66, 72 at both remote and local sites)before the system 50 is run in an actual control mode.

In the simulation mode, the local simulation module 67 replaces the testsubject (or patient), but all the other modules (e.g., modules at theremote site 70, 72, 74; safety and verification module 66 and localoperation module 65 at the local site) preferably operate in exactly thesame manner.

In one or more embodiments of the invention, the local operation andperformance simulation module 67 is configured to test the trackingfunctions of the local operation module 65 by replacing the test subjectwith a digitized fundus image of him or her. The tracking system istested using the digitized fundus image in place of the test subject bydisplacing the digitized fundus image in the X, Y, and O directions (seeFIG. 9). The displacement of the digitized fundus image simulates thehead and/or eye movement of the test subject that is experienced in theactual control mode. The laser is activated in the simulation mode, butis configured to turn off if the movement of the digitized fundus imageexceeds a certain predetermined threshold so as to simulate the actualmovement of the test subject exceeding a predetermined threshold.

Any rapid displacement beyond a certain predetermined threshold value orrange of values (e.g., an orientation change exceeding 3-5 degrees)cannot be immediately compensated for by the tracking system. As aresult, in such a situation, the local operation and performancesimulation module 67 is configured to simulate the response of thetracking system to the detection of a displacement exceeding thethreshold value or range by shutting down the laser of the lasercoagulation system. In the simulation mode, the digitized fundus imagecan be slightly tilted or laterally displaced (e.g., moving the image onthe screen of a visual display device or mechanically, by displacing thescreen itself containing the image with a multi-dimensional actuator) tosimulate the deactivation of the laser. In some embodiments, thetracking system is configured to follow a particular spot on the fundusimage. When the spot being followed by the tracking system is rapidlytilted or displaced, the laser is shut down by the laser coagulationsystem. This simulated test is used to ensure that the tracking systemis fully operational and functioning properly prior to the performanceof the laser surgery (i.e., in the actual control mode).

While performing the simulation using a digitized fundus image of theeye is preferred, a physical model of an eye can also be used to performthe simulation carried out by the local operation and performancesimulation module 67. For example, an artificial eye can be placed infront of the lens of the laser-imaging apparatus. In such an artificialeye, the retina of the eye is visible through the pupil thereof. In thisconfiguration, the tracking system of the laser coagulation system istested by slightly displacing the artificial eye in front of the lens ofthe laser-imaging apparatus (e.g., by using mechanical means, such as amulti-dimensional mechanical actuator) while the laser is activated, butis not firing any actual laser shots. When the detected displacementexceeds the threshold value or range, the tracking system is triggeredso as to shut down the laser.

Remote Operations Module

According to the invention, the remote operation module 70 provides thephysician with an interface to a personal computer. During a laserprocedure, some of the important tasks that the physician will perform(and are facilitated by the remote operation module) include: (1)screening via digitized photos, (2) outlining an oval area encompassingthe center part of the retina (see FIGS. 5 and 7), (3) choosing the spotsize and duration of laser application, (4) adjusting the power viasingle shots of test spots (preferably, with a duration in the range ofapproximately 0.001-0.1 seconds in approximately 0.06 intervals), (5)executing virtual treatment with the simulation module (see FIG. 6), (6)performing a test surgery, which involves the local operation andperformance simulation module 67, and (7) performing the laser surgeryin the actual control mode (and observing the surgery via a real-timevideo stream).

In one or more embodiments of the invention, the remote operation module70 further comprises an electronic visual display device withtouchscreen capabilities, which is operatively coupled to a personalcomputer or another digital appliance that has processing capabilities(e.g., a portable digital device, such as a mobile phone or smartphone,a laptop computing device, a palmtop computing device, a tabletcomputing device, etc.) As such, the laser-imaging apparatus (i.e., thefundus camera) is operatively coupled to the visual display device ofthe remote operation module 70 so that the digitized fundus (retinal)image of the patient is able to be displayed in detail.

The touchscreen system of the remote operation module 70 comprises adisplay screen that is sensitive to the touch of a finger or a type ofstylus (e.g., a pen stylus). The touchscreen-type visual display deviceincludes: (i) touch sensor in the form of a panel with a responsivesurface, (ii) a hardware-based controller, and (iii) touchscreensoftware executed by the personal computer or other digital appliance.The touch sensor employed by the touchscreen may comprise resistive-typesensor(s), capacitive-type sensor(s), or surface acoustic wavesensor(s). Each of these sensor types has an electrical current passingthrough them, and touching the surface of the screen results in aconsequential voltage change. The voltage change is indicative of thelocation of the touching. The controller is the hardware component thatconverts the voltage changes produced by the touch sensor into signalsthat the personal computer or other digital appliance can receive. Thetouchscreen software instructs the personal computer or other digitalappliance as to what is occurring on the touchscreen and on theinformation delivered from the controller (i.e., what the user istouching and the location of his or her touch) so that the computer ordigital appliance can respond accordingly.

Using the touchscreen visual display device, the physician (i.e., theophthalmologist) can control the laser system with the touch of his orher finger or by using a stylus pen, etc. The visual display device alsoincludes zoom capabilities in order to allow the physician to examinethe details of the digitized fundus image (i.e., retinal image) ifneeded. The display recognizes and interprets the commands of thephysician and communicates those commands to the personal computer thatcontrols the laser generation system. As such, the laser generationsystem is controlled in accordance with the markings made by thephysician on the touchscreen. In other words, the laser generationsystem is configured to carry out the laser treatment in accordance withthe indicated markings on the touchscreen. When a typical procedure isbeing carried out by the physician, the digitized fundus (retinal) imageof the patient is initially recalled on the visual display device.Because the fundus image is digitized, the physician is able toprecisely sketch/draw on any area of the digitized fundus image so thathe or she can indicate the location(s) where the laser pulses should beapplied, and as required, the location(s) where the laser pulses shouldnot be applied. For example, the area or areas where the laser pulsesare to be applied are shaded and/or denoted using a first predeterminedcolor (e.g., green, which signifies a laser is to be applied thereto),while the area or areas where laser pulses are not to be applied areshaded and/or denoted using a second predetermined color (e.g., red,which signifies that a laser is not to be applied in this region orregions). When the laser coagulation system is operating in either thesimulation mode or the actual control mode, any invasion of the areashaded with the second predetermined color (i.e., the red area) willresult in the immediate shutting down of the laser. Also, the area(s)where the laser pulses are to be applied can be separated from the restof the retina by a continuous line of a predetermined color (e.g., a redline) so that there is a clear demarcation on the retinal image. Thearea or areas that are shaded and/or denoted using the secondpredetermined color (i.e., red, indicating that laser pulses are not tobe applied thereto) may represent a part of the retina containing largeretinal vessels, such as the region with the optic nerve head and thefovea, which are sensitive to laser damage and should not be coagulated(e.g., see FIG. 11). The area of the laser coagulation can be contiguousor separated. In general, the distance between each of the laser pulsescan vary (e.g., in the range between 0.1 mm and 4.0 mm or betweenapproximately 0.1 mm and approximately 4.0 mm, inclusive). The laserapplication can be a single pulse as long as it is indicated by a singlecolored dot (e.g., a green dot), or the quantity of the laser spots canrange up to 2500 spots or more. The laser pulse duration can be in therange from one femtosecond to 4.0 seconds, inclusive (or in the rangefrom approximately one femtosecond to approximately 4.0 seconds,inclusive). In other embodiments, the laser pulse duration can exceed4.0 seconds. The energy level of each pulse can range from 0.01femtojoule to one joule, inclusive (or between approximately 0.01femtojoule to approximately one joule, inclusive), and more preferably,between 1 nanojoule to one joule, inclusive (or between approximately 1nanojoule to approximately one joule, inclusive). The spot size of thelaser varies between 0.0001 nanometers (nm) to 2 millimeters (mm),inclusive (or between approximately 0.0001 nm to approximately 2 mm,inclusive).

In addition, in one or more embodiments, the visual display device withtouchscreen capabilities displays the degree of energy (e.g., number oflaser pulses, laser spot size, laser power or laser energy level) andthe number of laser spots applied for a given area. The visual displaydevice also displays all the parameters that are needed or chosen by theoperator in addition to the presentation of the virtual image of thetest laser application. All of this information is recorded and storedin the computer. The remote laser apparatus, which is located at each ofthe local sites 51 a, 51 b, 51 c (see FIG. 5), does not perform thelaser coagulation if the prior test is not performed. Similarly, afterthe correction of any parameter of the laser, or any change in the areaof application of the laser, a new test application is run to ensure thesafety of the procedure.

Also, as a part of the fail safe mechanism of the system, any invasionof the area which is not be subjected to the laser (e.g., the areacolored in red by the physician) results in the immediate shutting downof the laser so that the appropriate inspection can be performed and/orcorrective actions can be taken. As such, the system has completecontrol over the area of laser application.

Referring now to FIGS. 7 and 8, there are shown photographs of theretina, showing the outline of the oval target area (area bound by twooval lines) thereon for application of laser spots (FIG. 7) and thelaser spots (in some embodiments, in the range of approximately 50-3000laser spots) on the retina achieved via virtual treatment (see FIG. 8),as described below. In some embodiments, the physician can draw the ovallines in FIGS. 7 and 8 on the digitized fundus image by utilizing thetouchscreen-type visual display device.

Now, turning to FIGS. 11-14, four (4) images showing exemplary areas oflaser application on a patient are illustrated (e.g., as marked by aphysician using the touchscreen-type visual display device). FIGS. 11-13depict laser application areas in the retina, which have been indicatedon the fundus (retinal) image of a patient, while FIG. 14 depicts alaser application area on the skin surface of a patient. Specifically,in FIG. 11, it can be seen that the annular area 300 (or donut-shapedarea 300) has been marked for laser application (e.g., by using a greencolor), while the central circular area 302 has been marked for no laserapplication thereto (e.g., by using a red color). As described above,the fovea 304 and the optic nerve head 306, which are located in thecentral circular area 302, are highly sensitive to laser damage, andthus, should not be coagulated. As shown in FIG. 11, the retinal areahas a plurality of blood vessels 308 disposed throughout; the retinalarea is surrounded by the or a serrata 310 (i.e., the serrated junctionbetween the retina and the ciliary body). Next, turning to FIG. 12, two(2) localized areas 312, 314 are marked for laser application (e.g., byusing a green color). As shown in FIG. 12, the localized areas 312, 314are generally elongated, curved regions of the retina. Then, withreference to FIG. 13, it can be seen that a plurality of singlelocalized spots 316 on the retina are marked for laser application(e.g., by using a green color). As illustrated in FIG. 13, the pluralityof localized spots 316 are disposed in close proximity to the fovea 304and the optic nerve head 306.

In addition, it is to be understood that the laser coagulation proceduredescribed herein can also be applied to external surface areas on thebody of a patient. For example, in FIG. 14, an area of skin lesion 320on a patient's face 318 is marked for laser application (e.g., by usinga green color). As other examples, the laser coagulation systemdescribed herein could be used to treat the eye surface, the cornea,conjunctiva, eyelid, skin areas, or visible mucosa. As such, any part ofthe eye can be treated with the laser coagulation system describedherein using the same laser-imaging apparatus described above, or amodified camera technology that is particularly suited for surfaceapplications (e.g., a standard camera, such as those that are used inphotography, or a microscope, etc.). Such a camera would be used tocreate images of the eye surface, the cornea, conjunctiva, eyelid, skinareas, or visible mucosa, etc.

Remote Operation and Performance Simulation Module

According to the invention, the remote operation and performancesimulation module 74 allows a physician or technician to perform virtualtreatment, which permits the physician to test the local operationmodule 65 (at a local site) in terms of its generation capability of thelaser spots throughout the surgery area specified by the doctor (seeFIG. 8). The algorithm used in this simulation module is similar to theone used by the local operation module 65.

After the physician (i.e., ophthalmologist) outlines the extent of thedesired treatment area using the touchscreen visual display device ofthe remote operation module 70, he or she initiates the simulationprocess using the remote operation and performance simulation module 74.The treatment area outlined by the physician is filled virtually by themodule 74 with dots (e.g., white dots), thereby covering the area andindicating the extent and the density of the laser spots that shouldoccur on the retina and not on any other area.

Referring now to FIG. 9, in some embodiments, movement of the object(i.e. digitized fundus photograph) is simulated via three randomvariables; X, Y and O. The variables X and Y denote the displacementchanges in the X and Y axes, respectively. The variable O denotes theorientation changes. In a preferred embodiment, the digitized fundusimage is displaced electronically by the remote operation andperformance simulation module 74 using the variables X, Y and O. Thedisplacement of the digitized fundus image represents the movement ofthe retinal image of the patient prior to operating the lasercoagulation system in the actual control mode.

In another embodiment, it is also possible to utilize mechanical meansto displace a hardcopy of the fundus image (e.g., by using amulti-dimensional mechanical actuator that is operatively coupled to thehardcopy of the fundus photograph).

To this end, movement data from test subjects is first collected, fromwhich best-fit statistical distributions (and variances) for the threerandom variables (X, Y, and O) are determined. According to theinvention, a “goodness-of-fit” test can then be performed to test thevalidity of the distribution.

If a theoretical distribution (involving larger p-value in statisticalsense) exists, it will then be employed. Otherwise, an empiricaldistribution will be constructed and employed.

According to the invention, the remote operation and performancesimulation module 74 also allows the physician to test the localoperation module 67 (at a local site) in terms of its generationcapability of the laser spots without involving communications with thelocal control module 62.

Safety and Verification Modules

According to the invention, safety and verification modules 66, 72 existboth at the remote site 58 as well as each local site 52, 54, 56 toensure safe and effective operation of the system 50. In a preferredembodiment of the invention, several constraints are preferably imposedinto the system 50 (both hardware and software). In some embodiments,the constraints include (1) physical constraints, (2) logicalconstraints, and (3) medical constraints.

According to the invention, physical constraints ensure variousparameters or values (e.g., therapy beam power) in the laser system 50are within a permitted range. If any of the values are outside apermitted range, laser firing will be automatically locked andnotification of the unacceptable value(s) is transmitted to thephysician at the remote site, as well as the technician at the localsite.

Logical constraints are employed to ensure that a correct sequence ofoperational tasks is performed. For example, if a physician at a remotesite mistakenly commands 700-1000 laser spots of laser application tothe fundus before simulating the laser application in a simulation mode,the system will not execute the command and transmits a warning messageto the physician. In a preferred embodiment, Unified Modeling Language(UML) is incorporated into the system software and employed to specifythe logical constraints.

The medical constraints involve monitoring of the fundus of the testsubject(s) during the actual laser procedure operation. If it isdetected that the laser energy effect on the fundus is different fromwhat the physician expected or the laser energy is applied beyond thespecified area, laser energy transmission is immediately terminated.Notification of the issue is also transmitted to the physician at theremote site, as well as the physician or technician at the local site.

As indicated above, in some embodiments of the invention, the system 50also includes eye tracking and facial recognition means to ensure safeoperation.

System Software Platform

The software system that is employed to control the laser procedure(s)with the laser-imaging systems of the invention includes client/serverarchitecture and a TCP/IP communication protocol. The client/serverarchitecture comprises a computer science paradigm, where clients andservers are deemed separate software processes that can run on the sameor different computers.

In some embodiments, the software recognizes the computer at thesurgeon's site as a client, while the local control module at the remotepatient's site is recognized as a server.

According to the invention, communication by and between the remotecontrol module 64 and the local control module 62 is facilitated via webservices implemented in .NET remoting technology.

When a physician at a remote site sends a control or data acquisitioncommand, the command is first transmitted to the local control module 62(or server) through the .NET remoting interface. In response to thecommand, the local control module 62 controls hardware compartmentsthrough a hardware specific interface (e.g., RS-232C interface, parallelcommunication protocol).

The communication speed between the client and the server will depend onseveral factors such as 1) the distances between the client and theserver, 2) network traffic conditions, and 3) the size of data (e.g.,images) being transmitted.

As will readily be appreciated by one having ordinary skill in the art,the present invention provides numerous advantages compared to prior artmethods and systems for laser coagulation procedures. Among theadvantages are the following:

-   -   The provision of laser-imaging systems, which will significantly        reduce laser transmission and, hence, procedure time. For        example, the length of time for the laser photo-coagulation        treatment for diabetic retinopathy will be reduced from 30-60        minutes per procedure to only two minutes. In general, the        duration of a single laser pulse, plus the time it takes to        perform the subsequent laser application multiplied by the total        number of pulses required is equal to the overall procedure        time. The manner in which the pulses are applied in a        conventional contact system (e.g., using a contact lens        positioned on the cornea in order to see the fundus) requires        the physician (i.e., ophthalmologist) to perform the procedure        laser shot by laser shot (i.e., to place a single laser spot at        a desired location and then move on to the next location). When        performing the procedure on a patient that requires 1000-2000        laser spots, the laser coagulation procedure can easily take 30        minutes or more. The laser coagulation system disclosed herein        uses millisecond laser pulses (and in some cases, less than        millisecond pulses), and each subsequent laser shot is performed        automatically, in some embodiments, by utilizing an oscillating        mirror (e.g., oscillating mirror 220 described above) placed in        the path of the laser beam such that the laser beam is displaced        without requiring any manual means. In addition, the wide angle        camera employed in one or more embodiments described herein        enables the entire retina to be viewed, rather than just a small        portion thereof, thereby further reducing procedure time. As a        result of these enhanced features, the laser coagulation system        described herein substantially reduces the overall procedure        time. In one embodiment, the remote operation module of the        laser coagulation system is configured to perform a fully        automated and continuous laser coagulation procedure over the        entire area of the retina in a period of time no greater than        approximately 2 minutes (or no greater than 2 minutes) in an        actual control mode.    -   The provision of laser-imaging systems, which will also reduce        the probability of error associated with manual surgery (tremors        and misjudgments) via a more precise computerized control        mechanism, with additional fail-safe features, and a wider angle        imaging camera for retina diseases. This offers more choices for        various lasers with different wavelengths, intensities, and        action than was previously possible.    -   The provision of laser-imaging systems, which will also allow a        physician or surgeon to perform a procedure at a remote site,        via a high-speed reliable Internet® connection, thus eliminating        the need for the patient to travel a long distance to be treated        at a specialist's office or, in the case of military field care        or space exploration units, allowing patients to be treated        immediately on-site.    -   The laser coagulation system described herein is in the form of        a non-contact system that does not require the use of a contact        lens or any other device in contact with the eye of the patient.        The laser coagulation system embodied herein also does not        require the physician to indent any portion of the patient's eye        (i.e., no indenter or scleral depressor is required to indent        the peripheral portion of the patient's eye). As a result, the        patient is far more comfortable during the laser coagulation        procedure.

The cameras employed in the systems can also be equipped withappropriate diode lasers and filters for auto-fluorescence photographyand angiography of the retina.

One can also develop a miniature version of the system by using printingtechnology, such as inkjet, to generate and integrate the micro-opticalparts not only on hard substrates, but also on those that are flexible.Having a miniature or micro-system will allow further use of suchtechnology in hard to reach places.

Without departing from the spirit and scope of this invention, one ofordinary skill can make various changes and modifications to theinvention to adapt it to various usages and conditions. As such, thesechanges and modifications are properly, equitably, and intended to be,within the full range of equivalence of the following claims.

What is claimed is:
 1. A system for laser coagulation of an eyestructure or a body surface, comprising: a local control system disposedat a first location and a central control system disposed at a remotesite, said remote site being at a second location, said local controlsystem being operatively coupled to said central control system by meansof a computer network; at least a first laser-imaging system disposed atsaid first location, said laser-imaging system including a laser-imagingapparatus, a laser generation system, a photoacoustic system, a firstprocessor and a local control module; said laser-imaging apparatusincluding a wide angle digital image acquisition system with at leastone wide angle viewing camera configured to acquire a digitized image ofsaid eye structure or said body surface, said local control moduleincluding local operation, local operation and performance simulation,and local safety and verification sub-modules, said local operationsub-module configured to acquire said digitized image of said eyestructure or said body surface from said wide angle digital imageacquisition system and transmit said digitized image to said remotesite; said laser generation system including an aiming laser configuredto generate and transmit an aiming laser beam to said eye structure orsaid body surface, and a treatment laser configured to generate andtransmit at least a first coagulation laser beam to said eye structureor said body surface, and means for controlling said wide angle digitalimage acquisition system, said first coagulation laser beam of saidtreatment laser transmitting pulsed laser energy in the form of aplurality of pulses having a pulse duration in the range betweenapproximately one femtosecond and approximately four seconds, inclusive;said photoacoustic system being operatively coupled to said lasergeneration system, said photoacoustic system including an ultrasoundtransducer configured to detect acoustic waves that are generated as aresult of the absorption of energy by said eye structure or said bodysurface such that said photoacoustic system is able to determine atemperature of said eye structure or said body surface subjected to saidpulsed laser energy, said photoacoustic system further being configuredto control said laser generation system by maintaining said pulsed laserenergy of said first coagulation laser beam at a predetermined energylevel so as to produce a uniform coagulation of said eye structure orsaid body surface; said central control system including a secondprocessor and a remote control module, said remote control moduleincluding remote operation, remote operation and performance simulation,and remote safety and verification sub-modules; said remote operationsub-module being configured to facilitate communications between aremote physician and said second processor, and perform a lasercoagulation procedure on said eye structure or said body surface in anactual control mode in which said treatment laser is configured totransmit said first coagulation laser beam to said eye structure or saidbody surface, said remote operation sub-module including a computingdevice and a touchscreen interface operatively coupled to said computingdevice, said computing device configured to receive said digitized imageof said eye structure or said body surface from said laser-imagingapparatus and display said digitized image on said touchscreeninterface, said computing device further configured to receive andprocess a target laser treatment area or areas drawn on said digitizedimage of said eye structure or said body surface by said remotephysician using said touchscreen interface; and said local operationsub-module being further configured to receive said target lasertreatment area or areas drawn on said digitized image of said eyestructure or said body surface from said computing device of said remoteoperation sub-module, and determine a pattern of laser spots on saiddigitized image such that, in said actual control mode, said treatmentlaser transmits said first coagulation laser beam in accordance withsaid pattern of laser spots.
 2. The laser coagulation system accordingto claim 1, wherein said computing device is further configured toreceive and process a non-treatment area or areas drawn on saiddigitized image of said eye structure or said body surface by saidremote physician using said touchscreen interface, said non-treatmentarea or areas designating where laser treatment is not to be applied;and wherein, when operating in said actual control mode, said treatmentlaser is shut down by said local control module if said treatment laserenters said non-treatment area or areas.
 3. The laser coagulation systemaccording to claim 2, wherein said computing device is furtherconfigured to receive and process said target laser treatment area orareas drawn on said touchscreen interface using a first predeterminedcolor and said non-treatment area or areas using a second predeterminedcolor; and wherein, when operating in said actual control mode, saidlocal control module is additionally configured to control said lasergeneration system based upon said first and second predetermined colorsby allowing said treatment laser to be applied to said target lasertreatment area having said first predetermined color and shutting downsaid treatment laser if said treatment laser enters said non-treatmentarea or areas having said second predetermined color.
 4. The lasercoagulation system according to claim 1, wherein said touchscreeninterface is further configured to enable said remote physician to zoomin and out on said digitized image of said eye structure or said bodysurface.
 5. The laser coagulation system according to claim 1, whereinsaid touchscreen interface is further configured to display saidpredetermined energy level and the quantity of laser spots to be appliedto said target laser treatment area or areas by said treatment laser;and wherein, when operating in said actual control mode, said localcontrol module is additionally configured to control said lasergeneration system based upon said predetermined energy level and saidquantity of laser spots displayed on said touchscreen interface.
 6. Thelaser coagulation system according to claim 1, wherein said localcontrol system further includes first facial recognition means forverifying identity of a subject, and wherein said central control systemfurther includes second facial recognition means for verifying identityof said subject.
 7. The laser coagulation system according to claim 1,wherein said local control module is further configured to control saidlaser generation system based upon each of the following said targetlaser treatment area or areas drawn on said digitized image of said eyestructure or said body surface using said touchscreen interface: (i) anannular-shaped treatment area, (ii) a plurality of elongated treatmentareas that are spaced apart from one another, and (iii) a plurality ofsingle localized treatment spots.
 8. The laser coagulation systemaccording to claim 1, wherein said at least one wide angle viewingcamera of said wide angle digital image acquisition system provides afield of view in a range between approximately 150° and approximately200°.
 9. The laser coagulation system according to claim 1, wherein saidat least one wide angle viewing camera of said wide angle digital imageacquisition system comprises a concave mirror.
 10. The laser coagulationsystem according to claim 1, wherein said at least one wide angleviewing camera of said wide angle digital image acquisition systemcomprises an elliptical mirror.
 11. The laser coagulation systemaccording to claim 1, wherein said ultrasound transducer of saidphotoacoustic system comprises a transducer array configured todirectionally target a reception of said acoustic waves.
 12. The lasercoagulation system according to claim 1, wherein said photoacousticsystem comprises an additional laser source configured to generate alight beam and to direct said light beam towards said eye structure orsaid body surface, said acoustic waves detected by said ultrasoundtransducer being generated as a result of the absorption of energy fromsaid light beam of said additional laser source by said eye structure orsaid body surface.
 13. The laser coagulation system according to claim12, wherein said photoacoustic system further comprises an objectivelens structure configured to be disposed between said additional lasersource and said eye structure or said body surface, said objective lensstructure configured to adjust a focusing direction of said light beamof said additional laser source so as to enable the localization of asource of acoustic signals, said objective lens being operativelycoupled to one or more micromechanical actuators, said one or moremicromechanical actuators configured to displace said objective lensrelative to said eye structure or said body surface so as to target aparticular line of points in said eye structure or said body surface.